Buchanan County’s trying a new method for building bridges that officials say can save money. The county’s built a bridge south of Independence using three railroad flatbed cars. Buchanan County Engineer Brian Keierleber says other states use the technique, mostly in the south.Keierleber says officials in Tama County built a bridge with railroad cars about 15 years ago. He says the bridges are great for low-traffic areas.The bridges can hold far more than the legal loads on the bridges. Keierleber says the bridges are cheaper than regular bridges as construction costs are cut way back.Keierleber says the county would like to build more of the railroad car bridges if they meet the county’s needs.